This is a list of some of the most common problems with Suzuki's automatic transmissions.
Harsh shifts, flares, and TCC issues
Suzuki XL7 cars with a 5-speed automatic transmission in the transverse configuration, designated as AF33-5, can develop various gear shift related issues. This ranges from harsh gear changes and failure to engage 5th gear to flares and harsh TCC engagement. Most of these symptoms will be intermittent and will not cause any warning lights.
- Excessive sleeve wears within the shift pressure control valve, which causes oscillations of the shift pressure. The resulting cross leaks will cause harsh shifts that are more noticeable on 2-3 and 3-4 upshifts. In some cases, there will be no 5th gear available. Installing an upgraded shift pressure control valve kit restores proper operation.
- Sticking linear solenoids, which causes inconsistent movement and causes pressure and flow drops or spikes. This results in flares and TCC apply issues and can even cause loud bangs while shifting gears. Installing new linear solenoids is the only reliable solution.
Harsh or delayed 2nd - 3rd shifts
Newer Grand Vitara models that use a 5-speed automatic transmission, designated as TB-50LS, suffer from a very specific issue that manifests itself as harsh or delayed gear shifts. The typical scenario involves such problems while upshifting from 2nd to 3rd on acceleration or on during downshifts when coasting. While there are no other symptoms in cases like these, a surge in engine speed may trigger a check engine light.
- Worn lockup control plunger components, which cause cross leaks and pressure drops and results in harsh torque converter clutch application. Being a well-known issue, there are various upgraded valve and sleeve kits available, which will restore proper operation.
- Excessive wear inside the accumulator control valve, causing leaks inside hydraulic passes and resulting in pressure losses. In most cases, harsh shifting will not be limited to 2-3 shifts and may affect other gear changes.
Shift flares and TCC issues
Most newer Suzuki cars use a 6-speed automatic transmission, designated as TF-80. There are several known issues that affect these transmissions, ranging from prominent shift flares during moderate accelerations or when coming to a stop to Torque Converter Clutch engagement issues in combination with harsh downshifts.
- Worn valve body bores, resulting in cross leaks and intermittent pressure losses. Depending on the location, worn patches can obstruct the solenoid movement. In both cases, this will cause delays in gear engagement and result in a flare. As this is a well-known issue, various transmission specialists offer refurbished valve bodies with uprated components.
- Excessive wear inside the TCC control bore, which allows pressure loss and results in TCC related issues. This can range from faulty TCC engagement, and harsh downshifts to surges in engine speed while coasting or on light acceleration. Reconditioning the bore and installing an oversized lockup clutch control valve kit solves these problems.
Whining and rattling on acceleration
While Suzuki models use different Continuously Variable Transmission versions, all of them can develop similar issues. These can range from a severe rattle and whining noise on acceleration to increased engine speed during acceleration combined with poor overall performance and fuel economy. In some cases, the engine will stall right after a startup.
- Pulley bearing failure, which is a well-known and wide-spread problem with these transmissions, causes rattle and whining noise. As there is a primary and secondary pulley bearing, tracking down the issue involves taking a test drive. If the tone and pitch of the noise changes during downshifts, the fault is with the primary pulley bearing. If there is constant during shifts, the secondary pulley bearing is a probable fault. There are aftermarket upgraded bearings available on the market.
- Excessive wear inside the TCC limit bore, which leads to pressure deviations and causes incorrect TCC control. This will usually result in an incorrect engine speed and poor fuel economy, while in some cases can even cause premature TCC lockups. Reconditioning the bore and installing an oversized kit will solve the issue.